Automatic transmissions generally include at least one planetary gear set and a plurality of shift elements. The shift elements selectively engage components of the planetary gear sets in order to hinder or prevent rotation of the components. Selective actuation of the shift elements adjusts the gear ratio of the automatic transmission and shifts the automatic transmission between its various gears.
Certain automatic transmissions include dog clutch shifting elements. During various gear shifts, the dog clutch is engaged or closed. Engaging the dog poses certain challenges. For example, the dog clutch is generally synchronized prior to engaging the dog clutch. When the dog clutch is synchronized, components of the dog clutch rotate at a common speed and may engage each other more easily. Conversely, such components may grind against each other and be damaged if the dog clutch is engaged while the dog clutch is not synchronized. However, synchronizing the dog clutch can be difficult and/or time consuming.
The automatic transmission may change gears and engage the dog clutch in a variety of circumstances. For example, when an associated vehicle is climbing a hill or rapidly accelerating, the automatic transmission may engage the dog clutch in order to downshift and change the gear ratio of the automatic transmission. As another example, the automatic transmission may engage the dog clutch when the vehicle is stopped or operating at a very slow speed in order to enter a forward gear or a reverse gear of the automatic transmission. Smoothly and/or quickly synchronizing and engaging the dog clutch when the associated vehicle is operating at such disparate speeds can be difficult.
Accordingly, a method for synchronizing a dog clutch of an automatic transmission would be useful. In particular, a method for synchronizing a dog clutch of an automatic transmission that also smoothly and/or quickly synchronizes the dog clutch in a variety of operating conditions would be useful.